PTFE is not melt-processable and therefore usually needs to be formed into the required shape prior to sintering. PTFE comprises both carbon and fluorine atoms, as a straight chain molecule, the carbon backbone being protected by a helix of the fluorine atoms wrapped around it. This carbon fluorine bond is one of the strongest chemical bonds and gives the material its properties of corrosion resistance and non-stick.
Chemically Inert PTFE resists the most aggressive organic and inorganic chemicals and solvents over a broad temperature range. This includes: Strong mineral acids Inorganic bases Inorganic oxidising agents Salt solutions Aldehydes Chlorocarbons Organic Acids Anhydrides Aromatics Alcohols Ketones Esters Fluorocarbons
Electrical Properties The ability to resist an electrical charge is measured by surface and volume resistivity. In the case of PTFE these figures are colossal. Depending upon how the test work is performed, values in excess of 1017Ω cm are considered minimum. In the case of equipment lined for the chemical and pharmaceutical industry this property can be a nuisance as PTFE lined equipment may build up electrostatic charges and be unable to dissipate them. This is considered elsewhere in relation to static-dissipating materials.
Low Friction PTFE has a very low coefficient of friction and for all calculation purposes it can be considered hydraulically smooth, Thermal Stability PTFE retains useful properties (i.e. not more than 15% loss of chemical resistance) at up to 200oC and sometimes beyond depending upon the application. In fact it has the highest retention of its chemical properties of any known plastic like material. (Please be wary of materials performance data stating that PTFE has an upper service limit of 260oC. This is true in a laboratory situation, but in service most material properties such as mechanical strength will have been lost preventing it from performing a useful duty.